高速CAN接口,TJA1050_3

handbook, halfpage
GND VCC RXD
2 3 4
TXD 1 GND 2
8 S 7 CANH CANL Vref
TJA1050T
VCC RXD 3 4
MGS375
6 5
Vref CANL CANH S
5 6 7 8
2002 May 16
3
Philips Semiconductors
PINNING SYMBOL TXD PIN 1 DESCRIPTION transmit data input; reads in data from the CAN controller to the bus line drivers ground supply voltage receive data output; reads out data from the bus lines to the CAN controller reference voltage output LOW-level CAN bus line HIGH-level CAN bus line select input for high-speed mode or silent mode Fig.2 Pin configuration.
TJA1050
The TJA1050 is the interface between the Controller Area Network (CAN) protocol controller and the physical bus. The device provides differential transmit capability to the bus and differential receive capability to the CAN controller. The TJA1050 is the third Philips high-speed CAN transceiver after the PCA82C250 and the PCA82C251. The most important differences are: • Much lower electromagnetic emission due to optimal matching of the output signals CANH and CANL • Improved behaviour in case of an unpowered node • No standby mode. This makes the TJA1050 eminently suitable for use in nodes that are in a power-down situation in partially powered networks.
High speed CAN transceiver
FEATURES • Fully compatible with the “ISO 11898” standard • High speed (up to 1 Mbaud) • Very low ElectroMagnetic Emission (EME) • Differential receiver with wide common-mode range for high ElectroMagnetic Immunity (EMI) • An unpowered node does not disturb the bus lines • Transmit Data (TXD) dominant time-out function • Silent mode in which the transmitter is disabled • Bus pins protected against transients in an automotive environment • Input levels compatible with 3.3 V and 5 V devices • Thermally protected • Short-circuit proof to battery and to ground • At least 110 nodes can be connected. QUICK REFERENCE DATA SYMBOL VCC VCANH VCANL Vi(dif)(bus) tPD(TXD-RXD) Tvj PARAMETER supply voltage DC voltage at pin CANH DC voltage at pin CANL differential bus input voltage propagation delay TXD to RXD virtual junction temperature 0 < VCC < 5.25 V; no time limit 0 < VCC < 5.25 V; no time limit dominant VS = 0 V; see Fig.7 CONDITIONS MIN. 4.75 −27 −27 1.5 − −40 GENERAL DESCRIPTION
Product specification
High speed CAN transceiver
FUNCTIONAL DESCRIPTION The TJA1050 is the interface between the CAN protocol controller and the physical bus. It is primarily intended for high-speed automotive applications using baud rates from 60 kbaud up to 1 Mbaud. It provides differential transmit capability to the bus and differential receiver capability to the CAN protocol controller. It is fully compatible to the “ISO 11898” standard. A current-limiting circuit protects the transmitter output stage from damage caused by accidental short-circuit to either positive or negative supply voltage, although power dissipation increases during this fault condition. A thermal protection circuit protects the IC from damage by switching off the transmitter if the junction temperature exceeds a value of approximately 165 °C. Because the transmitter dissipates most of the power, the power dissipation and temperature of the IC is reduced. All other IC functions continue to operate. The transmitter off-state resets when pin TXD goes HIGH. The thermal protection circuit is particularly needed when a bus line short-circuits. The pins CANH and CANL are protected from automotive electrical transients (according to “ISO 7637”; see Fig.4). Table 1 Function table of the CAN transceiver; X = don’t care VCC 4.75 to 5.25 V 4.75 to 5.25 V 4.75 to 5.25 V <2 V (not powered) 2 V < VCC < 4.75 V TXD 0 X 1 (or floating) X >2 V S 0 (or floating) 1 X X X CANH HIGH 0.5VCC 0.5VCC CANL LOW 0.5VCC 0.5VCC
MAX. 5.25 +40 +40 3 250 +150
UNIT V V V V ns °C
ORDERING INFORMATION TYPE NUMBER TJA1050T TJA1050U PACKAGE NAME SO8 − DESCRIPTION plastic small outline package; 8 leads; body width 3.9 mm bare die; die dimensions 1700 x 1280 x 380 µm VERSION SOT96-1 −
S
8
TXD
1
TXD DOMINANT TIME-OUT TIMER VCC
DRIVER 7 25 kΩ 0.5VCC GND
CANH
RXD
4
RECEIVER GND 5 REFERENCE VOLTAGE
25 kΩ 6 CANL
Vref
TJA1050
2
MGS374
GND
Fig.1 Block diagram.
2002 May 16
2
Philips Semiconபைடு நூலகம்uctors
Product specification